Process of producing double olefins.



- -mvirnn STATES PATENT OFFTQ FEITZ HOFMATTN AND LUDWIG TANK, OF ELBERFELD, GERMANY, ASSIGNORS T FARBENFABRIKEN VORM. FRIEDR. BAYER 8: 10., OF ELBERFELD, GERMANY, A

CORPORATION OF GERMANY.

PROCESS OF PRODUCING DOUBLE OLEFINS.

' i No Drawing.

To all whom it may concern:

Be it known that we, Fnrrz HOFMANN and LUDWIG TAN a, doctors of philosophy, chemists,.citizcns of the German Empire, residing at Elberfeld, Germany, have invented new and useful Improvements in Processes for Producing Double Olefins, of which the following is a specification.

It has been found that double olefins, like 10 erythrene and its homologues can readily be obtained by'heating above 500 C. cyclohexanols. Agents promoting the decomposition can be added. This process proceeds e. 9. according to the following equation:

CH-OH place immediately with a lively evolution of gas. v Water, cyclohexen'e and cyclohexanone and also a' small quantity of unchanged cyclohexanol distil over. The gases are then fixed by bromin or are directly condensed.

' Erythrene. is .thusobtained with a' good yield.

Example 2: 500 parts of ortho-methylcyclohexanol are converted intogas form in' a porcelain tube which is heated at 500- 40 600 C. and is filled with iron filings,a slight evolution of gas takes place. The cooled receiver contains hydrocarbons from which isoprene can be isolated by distillation.

Example 3: On replacing in Example 1 Specification of Letters Patent.

Application filed January 21, 1911. Serial No. 603,892.

Patented Nov. 28, 1911.

the cyclohexanolby oxymethylcyclohexane' 5 of the formula: v

, on con OH: I on, on,

CH2 v the process takes place in an analogous manner. Isoprene is obtained with a good yield. In this case the iron tube is filled with native aluminium sesquioxid.

Instead of the cyclohexane derivatives mentioned in the above examples other of these compounds can be used. I

We claim 1. The process for producing olefins with two double bonds, which process consists in heating above 500 C. cyclohexanols, substantially as described. v

2. The process for producing olefins with two double bonds, which process consists in heating above 500 C. cycloheiganols with the addition of an agent promoting the decomposition, substantially as described.

3. The process for producing isoprene, which process consists in heating above 500 C. methylcyclohexanol, substantially as described.

4. The process for producing isoprene, 75 which process consists in heating above 500 C. ,methylcyclohexanol with the addition of aii-agent promoting the decomposition; substantiallyas described. In testimony whereof we have hereunto so set our-hands in the presence of two subscribingwitnesses.

'- FRITZ HOFMANN. [L. s.] LUDWIG TANK. [n.5,]

Witnesses:

j WALTER OONNEGUT, ALFRED HENKEL. 

